The invention relates to an optical disk apparatus for enabling the use of two kinds of media of different shapes of a compact disc such as a CD-ROM or the like and a cartridge enclosed media such as a magneto-optical disk or the like by one apparatus and, more particularly, to an optical disk apparatus for enabling inputting/outputting processes as an individual apparatus for an upper host computer even if it is physically one apparatus.
A compact disc (CD) starting from an audio-use has been remarkably developed in ten and a few years and can be regarded as a leader for multimedia storage at present. Particularly, in recent years, a personal computer having therein a compact disc read only memory (hereinafter, simply referred to as a "CD-ROM") is widely available. It is regarded that the position of a CD player for reproducing a CD-ROM has been established as a third file device subsequent to a floppy disk drive (FDD) and a hard disk drive (HDD). On the other hand, a rewritable type optical disk apparatus using a magneto-optical disk enclosed in a cartridge is gradually gaining in popularity because it has a large capacity and it is removable. The use of such a rewritable optical disk apparatus is also being used as a file device using a magneto-optical disk cartridge (MO cartridge) of 5 or 3.5 inches according to the ISO.
In a device using such a conventional optical disk media, however, an exclusive-use drive exists therefor every kind of the optical disk media such as CD-ROM or MO cartridge. Therefore, when the user wants to use both the CD-ROM and the MO cartridge, a CD player and an MO drive have to be separately provided. Particularly, in recent years, in many cases, the CD player or MO drive is built in the apparatus main body as a peripheral device of a personal computer. In such a case, it is difficult in terms of the space to build two devices and there often only one of the two devices can be built in the apparatus main body. Toward a full-scale multimedia age, with respect to the CD player, demand is not limited to a simple reproducing apparatus of the CD-ROM, but a rewriting function which has already been realized in the MO drive is strongly demanded. With regard to the MO drive, on the other hand, demand is not limited to the use as a simple file device but it is strongly desired that the MO drive can cope with a CD-ROM, a video CD, and the like which are provided as a part of the multimedia environment. Particularly, when considering the MO drive, it is becoming an indispensable condition to have full CD resources provided in the field of a personal computer.
In the CD player, in addition to a conventional CD-DA for music and a CD-ROM for reproducing dictionary data, an image data program, and the like, the addition and storage of a large capacity of data using those media simultaneously become the necessary conditions. On the other hand, the MO drive using the readable, writable, and further removable MO cartridge having a large capacity according to the ISO is also a device that is indispensable for processing of a large amount of data which is provided by the CD-ROM or the like.